Study of serum levels of insulin-like growth factor -1, insulin - like growth factor bunding protein -1 and -3, prealbumin and aminoterminal propetide of type -1 procollagen in infants and children with protein energy malnutrition

Abstract

Protein energy malnutrition (PEM) is a range of pathological conditions arising from coincident deficiency of proteins and calories in varying proportions occurring mostly in infants and young children. <br/>According to Welcome classification, PEM is classified into mild form (underweight) and severe form (marasmus, kwashiorkor or marasmic kwashiorkor) (Wellcome, 1970). <br/>The assessment of nutritional condition may be done through clinical examination, anthropometric measures or biochemical tests. <br/>The insulin-like growth factors (IGFS), are defined as polypeptide growth factors secreted by the liver and other tissues in response to stimulation by growth hormone (GH) (Guyton, 1996). <br/>In humans, there are two main forms of IGFS: Irsulin-like growth foctor-1 (IGF-1) and insulin-like growth foctor-11 (IGF-11). The most important of these is IGF-1, its synthesis is GH dependent, and its plasma levels are very sensitive to changes in GH availability (Berne et al, 1998). <br/>The IGFS circulate in plasma in complex with a family of binding proteins that extend the serum half-life of the IGF peptides, transport the IGFS to target cells and modulate the interaction of the IGFS with surface membrane receptors (Reiter and Rosenfeld, 1998). <br/>There are six IGF - binding proteins (IGFBPS) designated IGFBP-1 to IGFBP-6. They are designated on the basis of their amino acid sequence (Berne et al, 1998). <br/>IGFBP-1 is generating much interest, because it possesses properties that are a typical for a classical binding protein. It is an important modulator of IGF activities (Martina et al, 1997). <br/>IGFBP-3 is the major IGFBP in the circulation (Boisclair et al, 2001). <br/>The prealbumin is a protein synthesized by the liver. It plays an important role in the plasma transport of vitamin A, and also involved in the transport of thyroid hormones (Silverman and Christenson, 1994) <br/>The aminoterminal peptide of procollagen, are removed during processing of collagen and released into the circulation. The level of procollagen peptides may provide a clinically useful index of growth (Raisz et al., 1998). <br/>-Aim of work : <br/>The aim of work is to evaluate serum levels of IGF-1 , IGFBP-1 , IGFBP-3 , prealbumin and aminoterminal propeptide of type 1 procollagen in malnourished children and demonstrate the effect of malnutrition on these parameters.